Cast aluminum and plastic hatch assemblies are well known. For example, such hatches are commercially available from Pompanette, Inc. of Charlestown, N.H., the assignee of the present invention. They are described in the U.S. Patent of A. Anderson entitled "Mechanism for Latching and Unlatching a Hatch Assembly", U.S. Pat. No. 5,566,992 which is assigned to the same assignee as the present invention. That application is included herein in its entirety by reference. Such assemblies typically include a cast aluminum alloy frame, an elastomeric gasket and a clear plastic cover. The hatch covers are typically made of a clear or tinted LEXAN sheet, a product of General Electric. These cast aluminum frames and clear plastic covers are however, susceptible to scratches during assembly, installation and removal of the assembly and when the cover is being removed or replaced by the owner of a vessel.
The prior art discloses a number of hinge assemblies which facilitate disassembly, as for example, the hinge disclosed in the U.S. Pat. No. 3,671,998 of Ruiz. The Ruiz patent discloses a hinge comprising first and second parts which move around an axis. The first part comprises two retractable pivots which can be inserted into a corresponding housing. The pivots are separated by a compression spring and are joined to a pin which slides along or within an oblong hole within a cylindrical body of the first part. This oblong hole has a slot to block the pin on each pivot in a locking position for taking the hinge to pieces.
Another hinge mechanism is disclosed by Persson, U.S. Pat. No. 5,274,882 entitled, "Hinge Mechanism". In the Persson device, a first hinge portion and a second hinge portion are urged toward predetermined angular relationships relative to one another, A force is applied by an axle which pivotally connects the first and second hinge portions to urge a V-shaped tip into a V-shaped groove in the second hinge portion. The first and second hinge portions are kept in a predetermined angular relationship until a torsional force overcomes the force which is keeping the V-shaped tip in the V-shaped groove.
The aforementioned hinge mechanisms may be useful for a number of applications, but apparently have not been accepted for marine hatch assemblies. It is believed that the aforementioned mechanisms have not been utilized for marine hatch assemblies be cause they have a number of drawbacks and do not provide a number of advantages which are inherent in the novel hatch assemblies disclosed herein. For example, the prior art devices are not completely suitable for a low profile installation of relatively simple construction.
It is also believed that there is a significant commercial demand for an improved marine hatch assembly in accordance with the present invention. Such assemblies have a relatively low profile, are of relatively simple construction and have a pleasing appearance. The hatch assemblies disclosed herein can be manufactured and sold at a competitive price, are durable and relatively free from maintenance. In addition, the hatch assemblies in accordance with the present invention facilitate the removal and replacement of a transparent or translucent hatch cover. The assemblies also minimize the likelihood of scratching or scaring the frame or lens during installation or removal from the vessel.